Hello neuro guys... I have an endoscopic third ventriculostomy planned soon, since a MRI and CSF Flow study have shown a moderately blocked aqueduct and little to no flow out of the third ventricle , and none out of the 4th. I have an arachnoid cyst next to (posterior) to the tectal plate but it is unclear if the AC is responsible for the narrowing of the aqueduct. My surgeon says the ETV is most appropriate at this time. Symptoms include pain/pressure, trouble focusing/memory/thought, gait/heavy weight feeling, burning behind the eyes.. Is leaving the AC alone a standard approach (size is 2.1 CM) ?